1. Field of the Invention
The present invention relates to a work vehicle which includes an operation lever pivoting forward and backward stepwise through a plurality of operation positions and a detent type retention mechanism holding the operation lever in each of the operation positions.
2. Description of Related Art
One example of such a work vehicle is a tractor described in Japanese Patent Laid-open Publication No. 2004-190697 (paragraphs [0027] to [0031], FIGS. 5, 7, and 8). The tractor includes, for example, a hand shift type operation lever (speed change lever), a lever support member supporting the operation lever such that the operation lever can pivot left and right via a second support shaft oriented in a front/back direction, and a support bracket supporting the lever support member such that the lever support member can pivot forward and backward via a first support shaft oriented in a left/right direction. The operation lever and the lever support member pivot integrally forward and backward with respect to the support bracket.
In addition, in the tractor, the support bracket includes a left wall having a fan shape in a lateral view and provided fixated to a left rear wheel fender. A plurality of engagement recesses corresponding to each operation position of the operation lever are provided on a top edge of the left wall. The lever support member includes, at a top end, a swing arm biased by a spring to swing downward around a support shaft oriented in the left/right direction. The swing arm includes an engagement pin on a free end. Accordingly, when the operation lever is operated to a desired operation position, the operation lever-side engagement pin fits into the engagement recess, of the plurality of engagement recesses provided to the support bracket, which corresponds to the operation position of the operation lever, and the operation lever is held at the desired operation position.
In other words, in the tractor described in Japanese Patent Laid-open Publication No. 2004-190697, the hand shift type operation lever and the detent type retention mechanism holding the operation lever in each of the operation positions are arranged so as to be aligned in the left/right direction and are integrally configured by the hand shift type operation lever, the lever support member pivoting forward and backward integrally with the operation lever, the left wall of the support bracket which includes the plurality of engagement recesses, and the swing arm provided to the lever support member, for example.
In the above-noted configuration, there is an increase in a left/right direction width of a stepwise position retaining type lever module configured by the operation lever and detent type retention mechanism, for example, which requires a space that is broad in the left/right direction as an installation space for the lever module. Therefore, an installation location of the stepwise position retaining type lever module is limited to locations having a broad space in the left/right direction, and there is room for improvement in teens of improving a degree of freedom in installing the various operation levers.
Specifically, development of a stepwise position retaining type lever module having favorable improvement of the degree of freedom in installation of various operation levers is desired.